Engines sometimes use fuel injection systems to introduce fuel into the combustion chambers of the engine. Fuel injection systems may include a number of fuel injectors, which may include solenoid operated valve assemblies for controlling the flow of fuel. A solenoid operated valve assembly may include a solenoid and an associated valve. The solenoid may include an armature, a biasing spring, and a solenoid coil, which acts as a magnet when provided with current.
When the solenoid coil is provided with current, a toroidal field of magnetic flux develops rapidly. The flux transfers to the stator core, in order to actuate the valve. Ideally the flux would remain confined to the stator core material. However, the magnetic flux may transfer to other components, such as, for example, the biasing spring, valve body, valve housing, etc. Relative movement between the electrically conductive biasing spring and the magnetic field may result in an induced voltage in the biasing spring. The induced voltage may result in current flow through valve members of the solenoid controlled valve assembly. Relative movement of cooperating valve members may then cause spark discharge or arcing, which may result in pitting of one or more of the valve members.
Systems have been developed for controlling electrical current in solenoid operated valves. For example, U.S. Pat. No. 6,598,852 (the '852 patent) issued to Tomoda, et al., discloses a solenoid valve assembly including a spring configured to complete a circuit through various stationary components of the valve assembly, for grounding a solenoid coil. While the system of the '852 patent may include means for grounding the solenoid coil, the system does not include structure for grounding elements in connection with a return spring (a.k.a. a biasing spring). Therefore, magnetic flux that transfers to the return spring could still cause arcing between a valve element and valve seats.
The present disclosure is directed to overcoming one or more of the problems discussed above.